macOS 27 Golden Gate Design

Design contract

Make the app look like a native macOS 27 app, not a web dashboard placed inside a Mac window.

The window is already the outer container. Do not add a rounded app shell inside it.
Start with a structural card budget of zero. Add a framed container only when a genuinely self-contained object's boundary communicates meaning.
Sidebars, content columns, inspectors, tables, lists, and forms are panes or content regions, not cards.
Let adjacent panes meet at a shared boundary. Use native dividers, separators, alignment, spacing, typography, and selection fills instead of nested rounded rectangles.
Keep Liquid Glass, but concentrate it in system chrome and compact controls: titlebar and toolbar controls, search, sidebar or inspector material, floating controls, popovers, menus, sheets, and transient surfaces.
Keep the primary content plane calm and readable. Do not put glass behind every row, section, or data block.
Prefer standard SwiftUI or AppKit components so macOS supplies current metrics, appearance, interaction, inactive-window behavior, accessibility adaptation, and future refinements.
Treat a selected row as a state treatment, not as evidence that every neighboring row needs a capsule.

If a layout violates these defaults, explain the semantic reason before keeping the extra container or glass surface.